The research is to study the enzymatic and nonenzymatic reactions of glyoxylate and other compounds involved in glyoxylate metabolism. The enzymatic work is concerned with reduction and oxidation of glyoxylate to glycolate and oxalate, respectively. These reactions are catalyzed in mammalian systems by lactate dehydrogenases, utilizing diphosphopyridine nucleotide as the coenzyme. The biological catabolism of the anesthetic methoxyflurane is studied to define its enzymatic decomposition to oxalate, presumably through glyoxylate as an intermediate. The nonenzymatic reactions of glyoxylate under study simulate the enzymatic reactions. Glyoxylate reacts with diphosphopyridine nucleotide analogs in the presence of an amine to yield stable condensation products. The mechanism of formation and the structures of the products are under investigation.